MELBOURNE — Australia and Japan signed contracts on Saturday for the delivery of the first three Mogami-class frigates as part of a fleet of Japanese-designed warships valued at A$10 billion (US$6.5 billion). Mitsubishi Heavy Industries will build the first three vessels in Japan, while Australia plans to construct another eight at a shipyard in Western Australia.

Japanese Defense Minister Shinjiro Koizumi and Australian Defense Minister Richard Marles attended a signing ceremony aboard the Mogami-class frigate JS Kumano docked off Melbourne. The first frigate is due to arrive in Australia in 2029.

Marles said the Japanese frigates were a major step toward delivering Australia with a larger and more lethal surface combat fleet, and that the announced timeframe is the fastest acquisition of a surface combatant into service in the Royal Australian Navy. He said Australia welcomed Japan's relaxation of export controls on defense equipment and technology with trusted partners like Australia. Marles also said Japan is an industrial powerhouse offering opportunity for Australia and the development of Australia's defense industry as represented by the Mogami project.

Koizumi said the introduction of Japanese vessels into the Australian navy represents a major step to elevate bilateral defense cooperation. He said a decisive factor in Australia choosing the Japanese frigate was that it could be operated with just 90 personnel, around half the crew of Australia's ANZAC-class frigates, which the new fleet is intended to replace. The Mogami-class frigates will be crewed by 92 sailors and officers and, according to Australia, will be equipped with surface-to-air and anti-shipping missiles and capable of operating combat helicopters.

In August 2025, Australia announced that the Japanese bid had won the contract to supply its next-generation general purpose frigates over Germany's MEKO A-200 from Thyssenkrupp Marine Systems. The warship deal gave a boost to Japan's defense industry, which had lost out on Australia's submarine contract to a French company in 2016.

JS Kumano participated in the recent Exercise Kakadu, a biennial multinational maritime drill hosted by Australia. Japan has been accelerating its military buildup while expanding its defense ties beyond the United States, and now considers Australia to be a semi-ally.

A new Australian defense strategy announced in recent days will add A$53 billion to the defense budget over a decade. Koizumi said Japan continued to be Australia's indispensable partner in the new defense strategy.